1. Field of the Invention
The present invention relates to a mechanical component, a mechanical component manufacturing method, a movement, and a timepiece.
2. Description of the Related Art
A precision machine such as a mechanical timepiece employs a mechanical component like a cogwheel which rotates with a shaft member.
FIG. 23 shows an example of a structure connecting a mechanical component and a shaft member (See, for example, EP-A-1708045 (Patent Literature 1)).
FIG. 23 shows a mechanical component 90 which has, at the center of a component main body 91 formed of a brittle material, a central hole portion 94 into which a shaft member 30 is forced and which is of a triangular configuration in planar view; and in close proximity to each side of the central hole portion 94, there is formed a slit-like opening 92.
Bridge portions 93 between the central hole portion 94 and the opening 92 retain the shaft member 30 due to their elasticity. A mechanical component of this type is formed thin, so that it is subject to the stress generated when the shaft member is forced in; in the mechanical component 90, however, it is possible to mitigate the stress due to the elasticity of the bridge portions 93.
In the mechanical component 90, however, the bridge portions 93 are subject to breakage due to the forcing-in of the shaft member 30.
A reduction in the elastic deformation amount of the bridge portions 93 might make the bridge portions 93 less subject to breakage; in that case, however, there is a fear of the fixation of the mechanical component 90 to the shaft member 30 being rather insufficient.